Electronic device and latch mechanism

ABSTRACT

A latch mechanism includes a latch and a rotation shaft supporting part. The latch is rotatable around a rotation shaft between a housing position and a lock position, and fixes a first unit and a second unit in a closed state at the lock position. The rotation shaft supporting part rotatably supports the rotation shaft. The latch has a first ring-shaped part disposed coaxially with the rotation shaft. The rotation shaft supporting part has a second ring-shaped part disposed coaxially with the rotation shaft. Heights of the first ring-shaped part and the second ring-shaped part are set such that an area of abutment between the first ring-shaped part and the second ring-shaped part increases as the latch rotates from the lock position to the housing position.

BACKGROUND

This is a continuation under 35 USC § 120 of U.S. application Ser. No.16/722,336, filed on Dec. 20, 2019, which is a continuation of U.S.application Ser. No. 15/951,443, filed on Apr. 12, 2018, which is acontinuation of International Application No. PCT/JP2016/003502, filedon Jul. 28, 2016, which claims priority to Japanese Application No.2015-218848, filed on Nov. 6, 2015, the entire disclosures of which areincorporated herein by reference.

1. Technical Field

The present disclosure relates to a latch mechanism that holds a secondunit in a closed state with respect to a first unit in an electronicdevice, and an electronic device including the latch mechanism.

2. Description of the Related Art

PTL 1 discloses an electric device including a main body, a display, anda latch mechanism. The display is pivoted to the main body freelyopenably. The latch mechanism locks the display in a closed state whenthe display is closed with respect to the main body. This latchmechanism includes a lock pawl, a latch, a biasing part, and a lockpart. The lock pawl protrudes outward from a front end surface of themain body. The latch is mounted on a front end surface of the displayfreely rotatably such that the latch can engage with or disengage fromthe lock pawl. The biasing part elastically biases the latch in adirection in which the latch engages with the lock pawl. The lock partprohibits rotation of the above-described latch in a lock direction in astate in which the latch and the lock pawl are disengaged. In PTL 1, thelock part prevents the latch from being locked again when the latch isdisengaged. Accordingly, the latch mechanism excellent in operability isrealized without requiring use of a pop-up spring that causes anincrease in size and cost and deterioration in operability.

CITATION LIST Patent Literature

PTL 1: Unexamined Japanese Patent Publication No. H07-36569

SUMMARY

The present disclosure provides a latch mechanism that holds a secondunit in a closed state with respect to a first unit, and an electronicdevice including the latch mechanism.

In an aspect of the present disclosure, an electronic device including afirst unit and a second unit openable to the first unit includes a latchmechanism that fixes the second unit in a closed state with respect tothe first unit. The latch mechanism includes a latch and a rotationshaft supporting part. The latch is rotatable around a rotation shaftbetween a housing position and a lock position, and fixes the first unitand the second unit in a closed state at the lock position. The rotationshaft supporting part rotatably supports the rotation shaft. The latchhas a first ring-shaped part disposed coaxially with the rotation shaft.The rotation shaft supporting part has a second ring-shaped partdisposed coaxially with the rotation shaft. Heights of the firstring-shaped part and the second ring-shaped part are set such that anarea of abutment between the first ring-shaped part and the secondring-shaped part increases as the latch rotates from the lock positionto the housing position.

According to the latch mechanism of the present disclosure, the latchcan be fixed when the latch is unlocked, and vibration of the latch andnoise caused by the vibration can be suppressed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an information processing deviceaccording to a first exemplary embodiment of the present disclosure;

FIG. 2 is a perspective view of the information processing device in astate in which a second unit is closed with respect to a first unit;

FIG. 3 is a view showing a latch mechanism of the information processingdevice in a state in which a latch is locked;

FIG. 4 is a view showing the latch mechanism of the informationprocessing device in the state in which the latch is locked;

FIG. 5 is a perspective view of the latch;

FIG. 6A is a view explaining operation of the latch mechanism when thelatch is locked;

FIG. 6B is a view explaining the operation of the latch mechanism whenthe latch is locked;

FIG. 6C is a view explaining the operation of the latch mechanism whenthe latch is locked;

FIG. 7A is a view explaining operation of the latch mechanism when thelatch is unlocked;

FIG. 7B is a view explaining the operation of the latch mechanism whenthe latch is unlocked;

FIG. 7C is a view explaining the operation of the latch mechanism whenthe latch is unlocked;

FIG. 8 is a view showing an internal configuration of the latchmechanism;

FIG. 9 is a view explaining the latch, a shaft, and a rotation shaftsupporting part;

FIG. 10 is a view explaining the latch, the rotation shaft supportingpart, and a spring (a biasing member);

FIG. 11 is a sectional view (a horizontal sectional view) for explainingthe configuration of the latch mechanism;

FIG. 12 is a sectional view (a vertical sectional view) for explainingthe configuration of the latch mechanism;

FIG. 13 is a view explaining a recess that houses the latch in the firstunit;

FIG. 14 is a view explaining a connection state between the shaft andthe rotation shaft supporting part in the first unit;

FIG. 15 is a view for explaining operation of the latch;

FIG. 16 is a view for explaining ring-shaped parts, that regulaterotation of the latch, respectively provided in the latch and therotation shaft supporting part (a shaft holding part);

FIG. 17 is a view explaining structural characteristics of thering-shaped parts;

FIG. 18 is a view explaining states of two ring-shaped parts when thelatch is in a closed state;

FIG. 19 is a view explaining states of the two ring-shaped parts whenthe latch is in an opened state; and

FIGS. 20A and 20B are views explaining a general application ofring-shaped parts that suppress rotation.

DETAILED DESCRIPTION

Hereinafter, exemplary embodiments are described in detail withreference to the drawings as appropriate. However, detailed descriptionbeyond necessity may be omitted. For example, detailed description of amatter that has been already known well or overlapping description ofsubstantially the same configuration may be omitted. This is to avoidunnecessary redundancy of the following description and to facilitateunderstanding by those skilled in the art.

Note that the inventors of the present disclosure provide the attacheddrawings and the following description for those skilled in the art tofully understand the present disclosure, and do not intend to limit thesubject matter as described in the appended claims by these drawings anddescription.

First Exemplary Embodiment

[1-1. Entire Configuration]

FIG. 1 is a perspective view of an information processing deviceaccording to a first exemplary embodiment of the present disclosure. Theinformation processing device serves as an example of an electronicdevice. It should be noted that, hereinafter, description is given byappropriately using directions shown in FIG. 1 as directions of theinformation processing device.

As shown in FIG. 1 , information processing device 100 includes firstunit 101 and second unit 102. Second unit 102 is detachable from firstunit 101. In a case where second unit 102 is attached to first unit 101,information processing device 100 can be utilized as a notebook typecomputer. Further, second unit 102 can be utilized alone as a tablettype computer. In this way, information processing device 100 is aso-called detachable type computer.

Second unit 102 alone has a function as the tablet type computer. Secondunit 102 includes display 121. Display 121 is configured, for example,with a liquid crystal display device, and is mounted on one principalsurface of second casing 120. Display 121 may be configured with anotherdisplay device, such as an organic EL device. Display 121 is providedwith a touch panel disposed on the liquid crystal display device andcapable of receiving user's touch operation. In order to realize thefunction as the computer, second unit 102 incorporates a centralprocessing unit (CPU), a volatile storage (RAM), a nonvolatile storage(ROM, SSD, or the like), a battery, and the like. The nonvolatilestorage (ROM, SSD, or the like) stores an operating system (OS), variousapplication programs, various data, and the like. The central processingunit (CPU) executes arithmetic processing by reading the OS, theapplication programs, and the various data, thereby realizing variousfunctions.

First unit 101 includes first casing 110, holder 130, and hinge 140.First casing 110 is formed of metal, such as magnesium alloy, or resin.First unit 101 includes an input part through which the user performsinput operation on the second unit. As the input part, first casing 110is provided with keyboard 111, touch pad 112, operation buttons 113, andthe like.

Holder 130 is electrically or mechanically connected with first unit101. Holder 130 attaches second unit 102 by housing a part of secondunit 102. When second unit 102 is attached, holder 130 electricallyconnects first unit 101 with second unit 102.

Hinge 140 couples holder 130 (i.e., second unit 102) and first unit 101such that holder 130 can rotate to first unit 101.

A connector (not shown) connected with a connector (not shown) of thesecond unit is provided within holder 130. Further, wiring forexchanging various signals or electric power between holder 130 andfirst unit 101 is passed through an inside of hinge 140. Various signalsand electric power can be given and received between first unit 101 andsecond unit 102 via these connectors and wiring.

FIG. 2 is a perspective view of information processing device 100 in astate in which second unit 102 is closed with respect to first unit 101.Connection terminals for connecting a power supply plug, an externaldevice, a memory card, and the like are provided on a side surface offirst unit 101. The respective connection terminals are provided withterminal covers such that the connection terminals are not exposed whenthe connection terminals are not used.

In the same way as first unit 101, second unit 102 is also provided witha connection terminal for the memory card, an earphone/microphoneconnection terminal, an HDMI (registered trademark) terminal, a USBterminal, and the like. A waterproof and dust-proof terminal cover isprovided for each of the terminals.

Further, information processing device 100 of the present exemplaryembodiment includes a latch mechanism for holding a state in whichsecond unit 102 is closed with respect to first unit 101. The latchmechanism includes latch 201 provided in first unit 101 and latchreceiver 202 provided in second unit 102. Latch 201 is formed ofmetallic material, such as magnesium. In first unit 101, latch 201 isdisposed in a center of a front side end of information processingdevice 100. In second unit 102, latch receiver 202 is provided in acenter of a front side end of information processing device 100 whensecond unit 102 is closed.

[1-2. Latch Mechanism]

[1-2-1. External Configuration of Latch Mechanism]

FIGS. 3 and 4 are views showing the latch mechanism in a state in whichlatch 201 is locked. FIG. 3 is a view of the latch mechanism as seenfrom a front of information processing device 100, and FIG. 4 is a viewof the latch mechanism as seen from obliquely above informationprocessing device 100.

Protrusions 221, 222 are provided on right and left within recess 42provided in second casing 120. Respective protrusions 221, 222 have lockholes 221 a, 222 a. In FIGS. 3 and 4 , lock holes 221 a, 222 a areprovided on upper surfaces of protrusions 221, 222. Lock holes 221 a,222 a are similarly provided on opposite surfaces (lower surfaces) ofprotrusions 221, 222. Since lock holes 221 a, 222 a are provided on bothsurfaces (a surface on which display 121 is disposed and its backsurface) of second unit 102 in this way, second unit 102 can be mountedon first unit 101 in any direction. In second casing 120, wall-shapedlock parts 42 a, 42 b are respectively provided on an upper side and alower side of recess 42.

FIG. 5 is a view showing a state in which latch 201 is unlocked andlatch 201 is released. Latch 201 is rotatably disposed around a rotationshaft within recess 40 provided in first casing 110. In latch 201,projections 201 a, 201 b that project in a radial direction of rotationare formed at ends on a side farthest from the rotation shaft. Further,protrusion 201 d (a lock part) that projects in a direction orthogonalto the radial direction of rotation is provided at an end on the sidefarthest from the rotation shaft of latch 201.

During unlocking, latch 201 is completely housed in recess 40 of firstunit 101 in a state in which latch 201 is maximally opened (rotated)downward. Hereinafter, a rotational position (a rotation angle) of latch201 when latch 201 is completely housed in recess 40 of first unit 101in the state in which latch 201 is maximally opened (rotated) downwardduring unlocking is referred to as a “first rotational position” or a“housing position”. Meanwhile, the rotational position (the rotationangle) of latch 201 when latch 201 is locked is referred to as a “secondrotational position” or a “lock position”. In the present exemplaryembodiment, when the first rotational position is set at 0 degrees, thesecond rotational position becomes 180 degrees.

[1-2-2. Lock Operation of Latch Mechanism]

Lock operation of latch 201 is described with reference to FIGS. 6A to6C. FIG. 6A shows a state in which latch 201 is located at the firstrotational position, that is, a state in which latch 201 is unlocked,while second unit 102 is closed to first unit 101. In order to locklatch 201 from this state, first, latch 201 is rotated until projections201 a, 201 b at tips abut on protrusions 221, 222 of second unit 102. Ina state in which projections 201 a, 201 b of latch 201 first abut onprotrusions 221, 222 of second unit 102, latch 201 is further pressedinto second unit 102 side. Then, projections 201 a, 201 b approach lockholes 221 a, 222 a while sliding on surfaces of protrusions 221, 222(see FIG. 6B). At this time, the rotation shaft of latch 201 is biasedupward by a biasing part (details are described below). Eventually, whenprojections 201 a, 201 b reach lock holes 221 a, 222 a of protrusions221, 222, projections 201 a, 201 b are inserted in lock holes 221 a, 222a by the biasing part (see FIG. 6C). Accordingly, latch 201 is locked.The rotational position of latch 201 at this time is the secondrotational position (the lock position).

Since projections 201 a, 201 b of latch 201 are inserted in lock holes221 a, 222 a of second unit 102 in a lock state, rotation of latch 201is regulated. In this state (see FIG. 6C), lock part 42 b on the lowerside of second unit 102 is located below protrusion 201 d of latch 201(in other words, lock part 42 b is located between protrusion 201 d andthe rotation shaft of latch 201). In order to open second unit 102 inthis state, it is necessary that protrusion 201 b is moved such thatlock part 42 b of second unit 102 is not regulated by protrusion 201 dof latch 201. However, since the rotation of latch 201 is regulated inthe lock state, protrusion 201 d of latch 201 cannot be moved. As aresult, second unit 102 cannot be opened, and second unit 102 is held ina closed state.

Unlock operation of latch 201 is described with reference to FIGS. 7A to7C. FIG. 7A is a view showing the lock state of latch 201. Latch 201 ismoved downward against biasing force of the biasing part (describedbelow) in this state (see FIG. 7B), and projections 201 a, 201 b areescaped from lock holes 221 a, 222 a. When projections 201 a, 201 b areescaped from lock holes 221 a, 222 a, latch 201 is rotated (opened)downward by its own weight (see FIG. 7C). With this configuration,protrusion 201 d of latch 201 is moved, and movement of lock part 42 bof second unit 102 is no longer prevented. Accordingly, second unit 102can be opened. In other words, latch 201 is unlocked. As describedabove, the latch mechanism of the present exemplary embodiment canrealize locking and unlocking of the latch by simple operation.

[1-2-3. Lock Mechanism]

Description is given of an internal configuration of the latch mechanismfor realizing the lock operation and the unlock operation of latch 201described above.

FIG. 8 is a view showing the internal configuration of the latchmechanism. FIGS. 9 and 10 are views explaining components around latch201. FIG. 11 is a sectional view (a horizontal sectional view) forexplaining the components for realizing the rotation of latch 201. FIG.12 is a sectional view (a vertical sectional view) for explaining thecomponents for realizing movement of latch 201 in an up and downdirection.

As shown in FIG. 8 , in first unit 101, rotation shaft supporting part31, spring 33 (one example of the biasing part), and spring supportingpart 35 are disposed on both sides of latch 201. Rotation shaftsupporting part 31 is formed of, for example, resin. As shown in FIGS. 9and 11 , shaft 21 passes through an inside of latch 201, and issupported by rotation shaft supporting parts 31 at both ends of latch201. With this configuration, latch 201 can rotate shaft 21 as therotation shaft. It should be noted that a caliber of a through-hole forshaft 21 in latch 201 is set at a value larger than a diameter of shaft21 such that friction of shaft 21 serving as the rotation shaft isreduced. Accordingly, latch 201 is opened (rotated) downward by its ownweight in a state in which latch 201 is not locked.

As shown in FIG. 9 , rotation shaft supporting part 31 has shaft holdingpart 31 a and spring mounting part 31 b. Shaft holding part 31 a holdsshaft 21. As shown in FIGS. 10 and 12 , spring mounting part 31 b ismounted with spring 33 for biasing rotation shaft supporting part 31 ina predetermined direction (a direction from spring 33 to rotation shaftsupporting part 31). Spring 33 is held by spring supporting part 35formed in first casing 110.

As described below, rotation shaft supporting part 31 is movable in thepredetermined direction or a direction opposite to the predetermineddirection. Hereinafter, regarding positions of rotation shaft supportingpart 31, a position at which rotation shaft supporting part 31 isfarthest from latch receiver 202 of second unit 102 in a state in whichsecond unit 102 is closed is referred to as a “first position”.Meanwhile, a position at which rotation shaft supporting part 31 cantake in a state in which latch 201 is locked is referred to as a “secondposition”. In other words, latch 201 is rotatable at least from thefirst rotational position to the second rotational position, androtation shaft supporting part 31 is movable at least from the firstposition to the second position.

FIG. 13 is a view explaining recess 40 that houses latch 201 in firstunit 101. Groove 41 formed in the up and down direction is provided onwalls 40 b, 40 c located on right and left sides of recess 40. FIG. 14is a view explaining rotation shaft supporting part 31 inserted ingrooves 41 and shaft 21 connected to rotation shaft supporting part 31.Rotation shaft supporting part 31 can move within grooves 41 upward ordownward according to the biasing force of spring 33 or force thatpresses down latch 201. It should be noted that the biasing force ofspring 33 must be a force capable of moving rotation shaft supportingpart 31 to the second position, in such a manner that projections 201 a,201 b of latch 201 can be inserted in lock holes 221 a, 222 a of secondunit 102 in the state in which latch 201 is locked.

By configuring the latch mechanism as described above, as shown in FIG.15 , latch 201 can be rotated around the rotation shaft (shaft 21), andthe rotation shaft can be moved upward and downward. Due to the rotationof latch 201 and the up and down movement, it is possible to realize thelock operation and the unlock operation of latch 201 by the simpleoperation explained in FIGS. 6A to 6C, 7A to 7C. As the latch mechanism,only latch 201 is sufficient for a part provided outside of a main body.The latch mechanism has a simple configuration, and does not require alarge space. As a result, the latch mechanism shown in the presentexemplary embodiment can be also mounted on a thin device.

[1-2-4. Rotation Suppressing Structure]

A rotation suppressing structure of latch 201 is described withreference to FIGS. 16 to 19 . As mentioned above, when latch 201 is notin the lock state, latch 201 can be freely rotated with shaft 21 as therotation shaft. As a result, in a case where information processingdevice 100 is used in an environment with much vibration, such as withina moving vehicle, latch 201 is vibrated and noise occurs. In the presentexemplary embodiment, in order to prevent vibration and noise, therotation suppressing structure is devised such that latch 201 is notvibrated when latch 201 is unlocked.

FIG. 16 is a view for explaining a configuration for suppressingrotation of latch 201. In order to suppress the rotation of latch 201,latch 201 is provided with ring-shaped part 27 disposed coaxially withshaft 21. Further, shaft holding part 31 a of rotation shaft supportingpart 31 is provided with ring-shaped part 37 disposed coaxially withshaft 21.

FIG. 17 is a view explaining structural characteristics of ring-shapedparts 27, 37. In FIG. 17 , (A) is an upper view of ring-shaped parts 27,37, and (B) is a side view of ring-shaped parts 27, 37. For example, asshown in (B) of FIG. 17 , ring-shaped parts 27, 37 are formed such thatheights are continuously changed (that is, so as to have gradients) in aheight direction. Specifically, ring-shaped parts 27, 37 are formed suchthat ring-shaped parts 27, 37 become highest at position B and becomelowest at position A symmetric to position B with a center of rings as areference.

FIG. 18 is a view explaining states of ring-shaped part 27 in latch 201and ring-shaped part 37 in rotation shaft supporting part 31 when latch201 is located at the second rotational position (the lock position).FIG. 19 is a view explaining states of two ring-shaped parts 27, 37 whenlatch 201 is located at the first rotational position (the housingposition). As shown in FIGS. 18 and 19 , the heights of ring-shaped part27 of the latch and ring-shaped part 37 of the rotation shaft supportingpart are set such that an area of abutment between ring-shaped part 27and ring-shaped part 37 increases as latch 201 rotates from the secondrotational position (the lock position) to the first rotational position(the housing position).

Specifically, as shown in FIG. 18 , respective ring-shaped parts 27, 37are formed such that, when latch 201 is located at the second rotationalposition (the lock position), a high portion of ring-shaped part 27opposes a low portion of ring-shaped part 37 of rotation shaftsupporting part 31, and a low portion of ring-shaped part 27 opposes ahigh portion of ring-shaped part 37. At this time, as shown in (B) ofFIG. 18 , a gap is formed between ring-shaped part 27 of latch 201 andring-shaped part 37 of rotation shaft supporting part 31. Accordingly,latch 201 can rotate without being blocked by ring-shaped parts 27, 37.

Since ring-shaped parts 27, 37 are formed as described above, when latch201 is rotated to the first rotational position (the housing position),the high portion of ring-shaped part 27 and the high portion ofring-shaped part 37 of rotation shaft supporting part 31 oppose to eachother (see FIG. 19 ). At this time, as shown in (B) of FIG. 19 , thehigh portion of ring-shaped part 27 of latch 201 and the high portion ofring-shaped part 37 of rotation shaft supporting part 31 abut on(interfere with) each other. Because of friction caused by this abutment(interference), the rotation of latch 201 is suppressed, and latch 201is fixed at the first rotational position (the housing position).

By above-described ring-shaped parts 27, 37, when the latch is locked,latch 201 can be freely rotated. On the other hand, when the latch isunlocked, latch 201 can be fixed at the housing position, and vibrationof the latch can be suppressed. In other words, the vibration of latch201 can be reduced without using a cushion or spring dedicated tovibration prevention, and occurrence of noise caused by the vibrationcan be suppressed. Accordingly, the configuration can be simplified, andminiaturization can be realized.

It should be noted that shapes of ring-shaped parts 27, 37 are notlimited to the structure shown in FIG. 17 . Ring-shaped parts 27, 37 mayhave a structure having a comparatively high portion and a comparativelylow portion. Moreover, the shapes (the heights) of ring-shaped parts 27,37 may be adjusted as follows. In other words, when latch 201 is locatedat or near the second rotational position (the lock position), acomparatively high portion (or a comparatively low portion) ofring-shaped part 27 of latch 201 and a comparatively low portion (or acomparatively high portion) of ring-shaped part 37 of rotation shaftsupporting part 31 oppose to each other. Also, when latch 201 is locatedat the first rotational position (the housing position), thecomparatively high portions of ring-shaped parts 27, 37 oppose to andabut on each other.

Further, the aforementioned ring-shaped rotation suppressing structurecan be applied not only to the latch mechanism but also to otherrotation mechanisms. In other words, as shown in FIGS. 20A and 20B, in acase where member A is rotatably coupled to member B, ring-shaped parts327, 337 may be respectively formed in member A and member B.Ring-shaped parts 327, 337 are disposed coaxially with rotation shaft321, and are changed so as to have gradients in a height direction. Inthis case, as shown in FIG. 20B, heights of ring-shaped parts 327, 337may be adjusted such that comparatively high portions of ring-shapedparts 327, 337 oppose to each other at a rotational position whererotation is desired to be suppressed.

[1-3. Effects etc.]

As described above, information processing device 100 of the presentexemplary embodiment is the electronic device including first unit 101and second unit 102 openable to first unit 101. Information processingdevice 100 includes latch mechanism (202, 201) that fixes second unit102 in the closed state with respect to first unit 101. The latchmechanism includes latch 201, rotation shaft supporting part 31, spring33 (one example of the biasing part), and lock holes 221 a, 222 a (oneexample of a second engagement part). Latch 201 is provided in firstunit 101, is provided with projections 201 a, 201 b (one example of afirst engagement part) at tips, and is rotatable around shaft 21 (oneexample of the rotation shaft) from the first rotational position to thesecond rotational position. Rotation shaft supporting part 31 isprovided in first unit 101, rotatably supports shaft 21, and is movablebetween the first position and the second position. Spring 33 isprovided in first unit 101, and biases rotation shaft supporting part 31in a direction from the first position to the second position. Lockholes 221 a, 222 a are provided in second unit 102, and are engageablewith projections 201 a, 201 b. Projections 201 a, 201 b and lock holes221 a, 222 a are engaged with each other when second unit 102 is in theclosed state with respect to first unit 101, rotation shaft supportingpart 31 is at the second position, and latch 201 is at the secondrotational position.

Due to the above-described latch mechanism, it is possible tolock/unlock the latch by the simple operation of rotation and up anddown movement. Further, since a number of parts provided outside of themain body can be reduced, the latch mechanism can be applied to a thinelectronic device.

In information processing device 100, latch 201 may include protrusion201 d (one example of a first lock part), and second unit 102 (secondcasing 120) may include lock part 42 b (one example of a second lockpart). Lock part 42 b is located between protrusion 201 d and therotation shaft (shaft 21) when second unit 102 is in the closed statewith respect to first unit 101 and latch 201 is located at the secondrotational position (that is, in the lock state). By a positionalrelation between protrusion 201 d and lock part 42 b, when latch 201 islocked, second unit 102 is prevented from being opened with respect tofirst unit 101.

Further, another aspect of the latch mechanism mounted on informationprocessing device 100 of the present exemplary embodiment includes latch201 and rotation shaft supporting part 31. Latch 201 is rotatable aroundthe rotation shaft (shaft 21) between the housing position and the lockposition, and fixes first unit 101 and second unit 102 in the closedstate at the lock position. Rotation shaft supporting part 31 rotatablysupports the rotation shaft. Latch 201 has first ring-shaped part 27disposed coaxially with the rotation shaft. Rotation shaft supportingpart 31 has second ring-shaped part 37 disposed coaxially with therotation shaft (shaft 21). Heights of the first ring-shaped part and thesecond ring-shaped part are set such that an area of abutment betweenfirst ring-shaped part 27 and second ring-shaped part 37 increases asthe latch rotates from the lock position to the housing position.

By the above-described ring-shaped parts, latch 201 can be fixed duringunlocking, and vibration of the latch can be suppressed. In other words,the vibration of latch 201 can be reduced without using a cushion orspring dedicated to vibration prevention, and occurrence of noise causedby the vibration can be suppressed. Accordingly, the configuration canbe simplified, and miniaturization can be realized.

Other Exemplary Embodiments

As above, the first exemplary embodiment is described as an illustrationof a technique disclosed in the present application. However, thetechnique in the present disclosure is not limited to this firstexemplary embodiment, and is also applicable to exemplary embodimentsthat are appropriately changed, replaced, added, omitted, or the like.Further, a new exemplary embodiment can be implemented by combining therespective components explained in the above-described first exemplaryembodiment. Therefore, other exemplary embodiments are described below.

In the first exemplary embodiment, latch 201 is provided on first unit101 side having the input part. However, latch 201 may be provided onsecond unit 102 side having the display.

In the first exemplary embodiment, the coil-shaped spring is used as thepart for biasing rotation shaft supporting part 31. However, the biasingpart is not limited to the coil-shaped spring. For example, a spring,such as a torsion spring or a plate spring, or an elastic member otherthan the spring may be used as the biasing part.

The shape of the projection, the protrusion, the lock part, the lockhole, or the like shown in the first exemplary embodiment is oneexample, and is not limited to the aforementioned shape. The shape ofthe projection, the protrusion, or the like may be any other shape if anidentical function is realized.

In the first exemplary embodiment, the so-called detachable typecomputer is described as an example of the electronic device. However,the idea of the present disclosure can be applied to other kinds ofelectronic devices. For example, the idea of the present disclosure canbe applied to an electronic device including an openable unit, such as anotebook type personal computer, a word processor, or an electronicdictionary.

As above, the exemplary embodiments are described as the illustration ofthe technique in the present disclosure. For that purpose, the attacheddrawings and the detailed description are provided.

Therefore, the components mentioned in the attached drawings and thedetailed description may include not only components that are essentialfor solving the problems, but also components that are not essential forsolving the problems to illustrate the above-described technique.Accordingly, those nonessential components should not be immediatelyrecognized as essential just because those nonessential components arementioned in the attached drawings or the detailed description.

Further, since the aforementioned exemplary embodiments illustrate thetechnique in the present disclosure, various changes, replacements,additions, omissions, or the like can be made in the claims and theirequivalents.

The present disclosure is useful for an electronic device including anopenable unit, such as a notebook type personal computer, a wordprocessor, or an electronic dictionary.

What is claimed is:
 1. An electronic device including a first unit and asecond unit openable to the first unit, the electronic devicecomprising: a latch mechanism that fixes the second unit in a closedstate with respect to the first unit, wherein the latch mechanismincludes: a latch rotatable around a rotation shaft between a housingposition and a lock position, the latch fixing the first unit and thesecond unit in the closed state at the lock position; and a rotationshaft supporting part that rotatably supports the rotation shaft, thelatch is disposed coaxially with the rotation shaft, and the rotationshaft supporting part is biased by a biasing part in a predetermineddirection.
 2. The electronic device according to claim 1, furthercomprising a biasing part supporting part that supports the biasingpart.
 3. The electronic device according to claim 2, wherein the biasingpart and the biasing part supporting part are disposed on each of bothsides of the rotation shaft.
 4. The electronic device according to claim1, wherein the first unit has an input part, and the second unit has adisplay.
 5. The electronic device according to claim 1, wherein theelectronic device is any of a notebook type personal computer, adetachable type computer, a word processor, and an electronicdictionary.